MLPPP Problem with Cisco 7513

Rodney Dunn rodunn at cisco.com
Wed Jan 7 14:16:10 UTC 2004


Richard,

One bug I know of that could possibly be a match is:

CSCec00268
Externally found severe defect: Resolved (R)
Input drops and * throttles on PPP multilink interface

fixed in 12.2(15)T9.  The way to verify is to check
'sh int multilink <x>' and see if the interface is under
throttle.

Router#sh int mu 2
Multilink2 is up, line protocol is up 
    <snip> 
Received 0 broadcasts, 0 runts, 0 giants, 0* throttles
                                           ^-- Here.

If that's not it email me offline and I'll help you get
it resolved.

Thanks,
Rodney

On Tue, Jan 06, 2004 at 05:30:51PM -0800, Richard J. Sears wrote:
> 
> I am hoping someone can shed some light on an interesting problem we are
> having - 
> 
> When we set up a customer for MLPPP, things tend to go well for a period
> of time. Then - all of a sudden - we will begin to have problems with
> our multilink bundles (generally only one at a time) and the only fix is
> to reload our 7513. This problem happens on both of our 7513 routers
> from time-to-time. Once we reload - the problem will stay gone for as
> long as several months, or in the last case only about 12 hours.
> 
> Once we see the problem, it is apparent only in one direction. For
> example the customer can push the full capacity of their circuits to us,
> but they cannot pull anything above about 300k back to them on a two-T1
> bundle. This is the same every single time we have the problem.
> 
> We have changed multilink bundles, tried different types of switching
> and route caching, turning on and off fragmentation - the only thing
> that solves the problem is reloading the entire router. We can pull the
> T1s from the multilink bundle and each individual T1 works great. No
> line errors, no crc errors - nothing. No errors are apparent while in
> MLPPP mode either. No throttles or anything similar.
> 
> We have had this problem in the past and it was recommended that we
> upgrade the code on our 7513s. We are currently running version
> 12.2(13)T5 on both our 7513 as well as the customers router. Upgrading
> the code did not solve the problem. I have been unable to locate a Cisco
> bug defining this type of problem for any version of their code.
> 
> This particular customer's T1s are both terminated on the same VIP (we
> are running DMLP) but are terminated on separate PAs and hence separate
> CT3s. We have noticed the problem even with T1 bundles on the exact same
> PA and CT3. We are not doing multi-chassis DMLP. dCEF is enable on both
> routers, however the problem remains the same even after disable dCEF.
> 
> Here are configs and router info:
> 
> interface Multilink6
>  description Eastgate Mall (s2/1/0/8:0 and s2/0/0/12:0) [20291]
>  ip address 207.158.1.133 255.255.255.252
>  no cdp enable
>  ppp multilink
>  ppp multilink interleave
>  multilink-group 6
> 
> interface Serial2/0/0/12:0
>  description Eastgate Mall #2
>  no ip address
>  encapsulation ppp
> no fair-queue
>  ppp multilink
>  multilink-group 6
> 
> interface Serial2/1/0/8:0
>  description Eastgate Mall #1
>  no ip address
>  encapsulation ppp
>  no fair-queue
>  ppp multilink
>  multilink-group 6
> 
> 
> AR04#sh diag 2    
> Slot 2:
>         Physical slot 2, ~physical slot 0xD, logical slot 2, CBus 0
>         Microcode Status 0x4
>         Master Enable, LED, WCS Loaded
>         Board is analyzed 
>         Pending I/O Status: None
>         EEPROM format version 1
>         VIP2 R5K controller, HW rev 2.02, board revision D0
>         Serial number: 17953368  Part number: 73-2167-05
>         Test history: 0x00        RMA number: 00-00-00
>         Flags: cisco 7000 board; 7500 compatible
> 
>         EEPROM contents (hex):
>           0x20: 01 1E 02 02 01 11 F2 58 49 08 77 05 00 00 00 00
>           0x30: 68 00 00 01 00 00 00 00 00 00 00 00 00 00 00 00
> 
>         Slot database information:
>         Flags: 0x4      Insertion time: 0x41C8 (1d08h ago)
> 
>         Controller Memory Size: 32 MBytes DRAM, 4096 KBytes SRAM
> 
>         PA Bay 0 Information:
>                 CT3 single wide PA, 1 port
>                 EEPROM format version 1
>                 HW rev 1.00, Board revision A0
>                 Serial number: 17814822  Part number: 73-3037-01 
> 
>         PA Bay 1 Information:
>                 CT3 single wide PA, 1 port
>                 EEPROM format version 1
>                 HW rev 1.00, Board revision A0
>                 Serial number: 09725065  Part number: 73-3037-01 
> 
>         --Boot log begin--
> 
> Cisco Internetwork Operating System Software 
> IOS (tm) VIP Software (SVIP-DW-M), Version 12.2(13)T5,  RELEASE SOFTWARE (fc1)
> TAC Support: http://www.cisco.com/tac
> Copyright (c) 1986-2003 by cisco Systems, Inc.
> Compiled Wed 28-May-03 21:57 by nmasa
> Image text-base: 0x60010930, data-base: 0x604C0000
> 
> 
> 
> AR04#sh ver       
> Cisco Internetwork Operating System Software 
> IOS (tm) RSP Software (RSP-JSV-M), Version 12.2(13)T5,  RELEASE SOFTWARE (fc1)
> TAC Support: http://www.cisco.com/tac
> Copyright (c) 1986-2003 by cisco Systems, Inc.
> Compiled Wed 28-May-03 22:00 by nmasa
> Image text-base: 0x60010948, data-base: 0x61F0A000
> 
> ROM: System Bootstrap, Version 11.1(8)CA1, EARLY DEPLOYMENT RELEASE SOFTWARE (fc1)
> 
> AR04 uptime is 1 day, 8 hours, 24 minutes
> System returned to ROM by reload at 09:45:48 UTC Tue Dec 23 2003
> System image file is "slot0:rsp-jsv-mz.122-13.T5.bin"
> 
> cisco RSP4 (R5000) processor with 262144K/2072K bytes of memory.
> R5000 CPU at 200Mhz, Implementation 35, Rev 2.1, 512KB L2 Cache
> Last reset from power-on
> G.703/E1 software, Version 1.0.
> G.703/JT2 software, Version 1.0.
> X.25 software, Version 3.0.0.
> SuperLAT software (copyright 1990 by Meridian Technology Corp).
> Bridging software.
> TN3270 Emulation software.
> Primary Rate ISDN software, Version 1.1.
> Chassis Interface.
> 3 VIP2 R5K controllers (2 FastEthernet)(6 Channelized T3).
> 2 FastEthernet/IEEE 802.3 interface(s)
> 168 Serial network interface(s)
> 6 Channelized T3 port(s)
> 123K bytes of non-volatile configuration memory.
> 
> 20480K bytes of Flash PCMCIA card at slot 0 (Sector size 128K).
> 8192K bytes of Flash internal SIMM (Sector size 256K).
> 
> Slave in slot 7 is running Cisco Internetwork Operating System Software 
> IOS (tm) RSP Software (RSP-DW-M), Version 12.2(13)T5,  RELEASE SOFTWARE (fc1)
> TAC Support: http://www.cisco.com/tac
> Copyright (c) 1986-2003 by cisco Systems, Inc.
> Compiled Wed 28-May-03 22:33 by nmasa
> Slave: Loaded from system 
> Slave: cisco RSP4 (R5000) processor with 262144K bytes of memory.
> 
> Configuration register is 0x2102
> 
> 
> 
> 
> 
> Any help would be greatly appreciated.
> 
> 
> ******************************************
> Richard J. Sears
> Vice President         
> American Digital Network                          
> ----------------------------------------------------
> rsears at adnc.com
> http://www.adnc.com
> ----------------------------------------------------
> 858.576.4272 - Phone
> 858.427.2401 - Fax
> ----------------------------------------------------
> 
> I fly because it releases my mind 
> from the tyranny of petty things . . 
> 
> 
> "Work like you don't need the money, love like you've
> never been hurt and dance like you do when nobody's
> watching."



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